Symposia
Improved Use of Research Evidence
Alexandra K. Gold, M.A.
Graduate Student
Massachusetts General Hospital
Boston, Massachusetts
Michael Otto, Ph.D.
Professor
Boston University
CAMBRIDGE, Massachusetts
Background: Substance use comorbidity is common among individuals with bipolar disorder (BD), affecting up to 60% of individuals with BD, and comorbid bipolar disorder and substance use disorders (BD+SUD) are associated with poorer clinical outcomes compared to BD alone. Despite worse clinical outcomes in the comorbid population, to date, there are no treatments that effectively target both the mood and substance use symptom domains among individuals with BD. Thus, assessing mechanisms that underlie comorbid BD+SUD may inform subsequent intervention development. We evaluated one hypothesized mechanism common to both BD and SUDs; this mechanism, impaired risk avoidance, describes a tendency to engage in a persistent pattern of risky behaviors (e.g., unsafe sexual behaviors, illegal activities) despite poor outcomes resulting from such behaviors.
Methods: Participants (N = 76) with BD (n = 45) and BD+SUDs (n = 31) in a relatively euthymic mood state completed a range of assessments that evaluated clinical risk behaviors and potential neurocognitive correlates of such behaviors (e.g., laboratory measures of risk avoidance).
Results: Overall, there were no significant differences in BD versus BD+SUDs across clinical and neurocognitive assessments, except that the BD+SUD group had higher self-reported executive dysfunction (p< .05). Collapsing across groups, we found that increased discounting of delayed rewards (β = 0.35, p < .001), older age (β = 0.50, p < .001), and an earlier age of (hypo)mania onset (β = -0.38, p < .004) predicted increased clinical risk behaviors.
Conclusions: Increased delay discounting, being older, and having an earlier age of (hypo)mania onset all predicted increased clinical risk behaviors in this sample. These findings reveal a potential mechanistic target, increased discounting of delayed rewards (e.g., devaluation of a reward with increasing time to reward receipt), that may be of relevance in BD and BD+SUDs. We explore the implications of this mechanism for treatment development in BD and BD+SUDs, respectively.